Knowledge of the future can not be acquired from the Gods or demons;nor
can it be obtained by comparisons or measurements orcalculations. Knowledge of the enemy is acquired only by humanagencies.

The
kinds of spies that are used are five in number: there are thenative spies, and there are the the spies within; there
are thespies that return from the other side; there are the spies of deathand the spies of life.

If all five
kinds of spies are employed, then nobody will ever learntheir secret ways; that is what we call a divine secret. It is
themost priceless possession of the Lord and master.

The lord and master must control his spies' work in person.
Thespies that return are those that render the best knowledge of theenemy, so show particular nobleness unto them.

1.
Sun Tzu said: Raising a host of a hundred thousand menand marching them great distances entails heavy loss on thepeople
and a drain on the resources of the State. The dailyexpenditure will amount to a thousand ounces of silver.

[Cf.
II. ss. ss. 1, 13, 14.]

There will be commotion at home and abroad, and men will dropdown exhausted on the highways.

"We
may be reminded of the saying: 'On serious ground, gather inplunder.' Why then should carriage and transportation causeexhaustion
on the highways?--The answer is, that not victualsalone, but all sorts of munitions of war have to be conveyed tothe
army. Besides, the injunction to 'forage on the enemy' onlymeans that when an army is deeply engaged in hostile territory,scarcity
of food must be provided against. Hence, without beingsolely dependent on the enemy for corn, we must forage in orderthat
there may be an uninterrupted flow of supplies. Then,again, there are places like salt deserts where provisions beingunobtainable,
supplies from home cannot be dispensed with."]

As many as seven hundred thousand families will be impeded intheir
labor.

[Mei Yao-ch`en says: "Men will be lacking at the plough-tail." The allusion is to the system of dividing
land into nineparts, each consisting of about 15 acres, the plot in the centerbeing cultivated on behalf of the State
by the tenants of theother eight. It was here also, so Tu Mu tells us, that theircottages were built and a well sunk,
to be used by all in common.

[See II. ss. 12, note.] In time of war, one of the families hadto serve in the army,
while the other seven contributed to itssupport. Thus, by a levy of 100,000 men (reckoning one able-bodied soldier
to each family) the husbandry of 700,000 familieswould be affected.]

2. Hostile armies may face each other for
years, strivingfor the victory which is decided in a single day. This being so,to remain in ignorance of the enemy's
condition simply becauseone grudges the outlay of a hundred ounces of silver in honorsand emoluments,

["For
spies" is of course the meaning, though it would spoilthe effect of this curiously elaborate exordium if spies wereactually
mentioned at this point.]

is the height of inhumanity.

[Sun Tzu's agreement is certainly ingenious. He begins
byadverting to the frightful misery and vast expenditure of bloodand treasure which war always brings in its train.
Now, unlessyou are kept informed of the enemy's condition, and are ready tostrike at the right moment, a war may drag
on for years. Theonly way to get this information is to employ spies, and it isimpossible to obtain trustworthy spies
unless they are properlypaid for their services. But it is surely false economy togrudge a comparatively trifling
amount for this purpose, whenevery day that the war lasts eats up an incalculably greater sum.

This grievous burden
falls on the shoulders of the poor, andhence Sun Tzu concludes that to neglect the use of spies isnothing less than
a crime against humanity.]

3. One who acts thus is no leader of men, no present helpto his sovereign, no master
of victory.

[This idea, that the true object of war is peace, has itsroot in the national temperament of the Chinese.
Even so farback as 597 B.C., these memorable words were uttered by PrinceChuang of the Ch`u State: "The [Chinese]
character for 'prowess'is made up of [the characters for] 'to stay' and 'a spear'(cessation of hostilities). Military
prowess is seen in therepression of cruelty, the calling in of weapons, thepreservation of the appointment of Heaven,
the firm establishmentof merit, the bestowal of happiness on the people, puttingharmony between the princes, the diffusion
of wealth."]

4. Thus, what enables the wise sovereign and the goodgeneral to strike and conquer, and achieve things
beyond thereach of ordinary men, is FOREKNOWLEDGE.

[That is, knowledge of the enemy's dispositions, and what hemeans
to do.]

5. Now this foreknowledge cannot be elicited from spirits;it cannot be obtained inductively from experience,

[Tu
Mu's note is: "[knowledge of the enemy] cannot begained by reasoning from other analogous cases."]

nor by any deductive
calculation.

[Li Ch`uan says: "Quantities like length, breadth,distance and magnitude, are susceptible of exact
mathematicaldetermination; human actions cannot be so calculated."]

6. Knowledge of the enemy's dispositions can
only beobtained from other men.

[Mei Yao-ch`en has rather an interesting note: "Knowledgeof the spirit-world
is to be obtained by divination; informationin natural science may be sought by inductive reasoning; the lawsof the
universe can be verified by mathematical calculation: butthe dispositions of an enemy are ascertainable through spies
andspies alone."]

7. Hence the use of spies, of whom there are five classes:(1) Local spies; (2) inward spies;
(3) converted spies; (4)doomed spies; (5) surviving spies.8. When these five kinds of spy are all at work, none candiscover
the secret system. This is called "divine manipulationof the threads." It is the sovereign's most precious faculty.

[Cromwell,
one of the greatest and most practical of allcavalry leaders, had officers styled 'scout masters,' whosebusiness it
was to collect all possible information regarding theenemy, through scouts and spies, etc., and much of his success inwar
was traceable to the previous knowledge of the enemy's movesthus gained." [1] ]

9. Having LOCAL SPIES means employing
the services of theinhabitants of a district.

[Tu Mu says: "In the enemy's country, win people over bykind
treatment, and use them as spies."]

10. Having INWARD SPIES, making use of officials of theenemy.

[Tu Mu
enumerates the following classes as likely to do goodservice in this respect: "Worthy men who have been degraded fromoffice,
criminals who have undergone punishment; also, favoriteconcubines who are greedy for gold, men who are aggrieved atbeing
in subordinate positions, or who have been passed over inthe distribution of posts, others who are anxious that their
sideshould be defeated in order that they may have a chance ofdisplaying their ability and talents, fickle turncoats
who alwayswant to have a foot in each boat. Officials of these severalkinds," he continues, "should be secretly approached
and bound toone's interests by means of rich presents. In this way you willbe able to find out the state of affairs
in the enemy's country,ascertain the plans that are being formed against you, andmoreover disturb the harmony and
create a breach between thesovereign and his ministers." The necessity for extreme caution,however, in dealing with
"inward spies," appears from anhistorical incident related by Ho Shih: "Lo Shang, Governor ofI-Chou, sent his general
Wei Po to attack the rebel Li Hsiung ofShu in his stronghold at P`i. After each side had experienced anumber of victories
and defeats, Li Hsiung had recourse to theservices of a certain P`o-t`ai, a native of Wu-tu. He began tohave him whipped
until the blood came, and then sent him off toLo Shang, whom he was to delude by offering to cooperate with himfrom
inside the city, and to give a fire signal at the rightmoment for making a general assault. Lo Shang, confiding inthese
promises, march out all his best troops, and placed Wei Poand others at their head with orders to attack at P`o-t`ai'sbidding.
Meanwhile, Li Hsiung's general, Li Hsiang, had preparedan ambuscade on their line of march; and P`o-t`ai, having rearedlong
scaling-ladders against the city walls, now lighted thebeacon-fire. Wei Po's men raced up on seeing the signal andbegan
climbing the ladders as fast as they could, while otherswere drawn up by ropes lowered from above. More than a hundredof
Lo Shang's soldiers entered the city in this way, every one ofwhom was forthwith beheaded. Li Hsiung then charged with
all hisforces, both inside and outside the city, and routed the enemycompletely." [This happened in 303 A.D. I do
not know where HoShih got the story from. It is not given in the biography of LiHsiung or that of his father Li T`e,
CHIN SHU, ch. 120, 121.]

11. Having CONVERTED SPIES, getting hold of the enemy'sspies and using them for our own
purposes.

[By means of heavy bribes and liberal promises detachingthem from the enemy's service, and inducing them
to carry backfalse information as well as to spy in turn on their owncountrymen. On the other hand, Hsiao Shih-hsien
says that wepretend not to have detected him, but contrive to let him carryaway a false impression of what is going
on. Several of thecommentators accept this as an alternative definition; but thatit is not what Sun Tzu meant is conclusively
proved by hissubsequent remarks about treating the converted spy generously(ss. 21 sqq.). Ho Shih notes three occasions
on which convertedspies were used with conspicuous success: (1) by T`ien Tan inhis defense of Chi-mo (see supra, p.
90); (2) by Chao She on hismarch to O-yu (see p. 57); and by the wily Fan Chu in 260 B.C.,when Lien P`o was conducting
a defensive campaign against Ch`in.The King of Chao strongly disapproved of Lien P`o's cautious anddilatory methods,
which had been unable to avert a series ofminor disasters, and therefore lent a ready ear to the reports ofhis spies,
who had secretly gone over to the enemy and werealready in Fan Chu's pay. They said: "The only thing whichcauses Ch`in
anxiety is lest Chao Kua should be made general.Lien P`o they consider an easy opponent, who is sure to bevanquished
in the long run." Now this Chao Kua was a sun of thefamous Chao She. From his boyhood, he had been wholly engrossedin
the study of war and military matters, until at last he cameto believe that there was no commander in the whole Empire
whocould stand against him. His father was much disquieted by thisoverweening conceit, and the flippancy with which
he spoke ofsuch a serious thing as war, and solemnly declared that if everKua was appointed general, he would bring
ruin on the armies ofChao. This was the man who, in spite of earnest protests fromhis own mother and the veteran statesman
Lin Hsiang-ju, was nowsent to succeed Lien P`o. Needless to say, he proved no matchfor the redoubtable Po Ch`i and
the great military power ofCh`in. He fell into a trap by which his army was divided intotwo and his communications
cut; and after a desperate resistancelasting 46 days, during which the famished soldiers devoured oneanother, he was
himself killed by an arrow, and his whole force,amounting, it is said, to 400,000 men, ruthlessly put to thesword.]

12.
Having DOOMED SPIES, doing certain things openly forpurposes of deception, and allowing our spies to know of them andreport
them to the enemy.

[Tu Yu gives the best exposition of the meaning: "Weostentatiously do thing calculated to deceive
our own spies, whomust be led to believe that they have been unwittingly disclosed.

Then, when these spies are
captured in the enemy's lines, theywill make an entirely false report, and the enemy will takemeasures accordingly,
only to find that we do something quitedifferent. The spies will thereupon be put to death." As anexample of doomed
spies, Ho Shih mentions the prisoners releasedby Pan Ch`ao in his campaign against Yarkand. (See p. 132.) Healso refers
to T`ang Chien, who in 630 A.D. was sent by T`aiTsung to lull the Turkish Kahn Chieh-li into fancied security,until
Li Ching was able to deliver a crushing blow against him.Chang Yu says that the Turks revenged themselves by killing T`angChien,
but this is a mistake, for we read in both the old and theNew T`ang History (ch. 58, fol. 2 and ch. 89, fol. 8respectively)
that he escaped and lived on until 656. Li I-chiplayed a somewhat similar part in 203 B.C., when sent by the Kingof
Han to open peaceful negotiations with Ch`i. He has certainlymore claim to be described a "doomed spy", for the king of
Ch`i,being subsequently attacked without warning by Han Hsin, andinfuriated by what he considered the treachery of
Li I-chi,ordered the unfortunate envoy to be boiled alive.]

13. SURVIVING SPIES, finally, are those who bring back
newsfrom the enemy's camp.

[This is the ordinary class of spies, properly so called,forming a regular part
of the army. Tu Mu says: "Your survivingspy must be a man of keen intellect, though in outward appearancea fool; of
shabby exterior, but with a will of iron. He must beactive, robust, endowed with physical strength and courage;thoroughly
accustomed to all sorts of dirty work, able to endurehunger and cold, and to put up with shame and ignominy." Ho Shihtells
the following story of Ta`hsi Wu of the Sui dynasty: "Whenhe was governor of Eastern Ch`in, Shen-wu of Ch`i made a hostilemovement
upon Sha-yuan. The Emperor T`ai Tsu [? Kao Tsu] sentTa-hsi Wu to spy upon the enemy. He was accompanied by two othermen.
All three were on horseback and wore the enemy's uniform.When it was dark, they dismounted a few hundred feet away fromthe
enemy's camp and stealthily crept up to listen, until theysucceeded in catching the passwords used in the army. Then theygot
on their horses again and boldly passed through the campunder the guise of night-watchmen; and more than once, happeningto
come across a soldier who was committing some breach ofdiscipline, they actually stopped to give the culprit a soundcudgeling!
Thus they managed to return with the fullest possibleinformation about the enemy's dispositions, and received warmcommendation
from the Emperor, who in consequence of their reportwas able to inflict a severe defeat on his adversary."]

14.
Hence it is that which none in the whole army are moreintimate relations to be maintained than with spies.

[Tu
Mu and Mei Yao-ch`en point out that the spy isprivileged to enter even the general's private sleeping-tent.]

None
should be more liberally rewarded. In no other businessshould greater secrecy be preserved.

[Tu Mu gives a graphic
touch: all communication with spiesshould be carried "mouth-to-ear." The following remarks on spiesmay be quoted from
Turenne, who made perhaps larger use of themthan any previous commander: "Spies are attached to those whogive them
most, he who pays them ill is never served. Theyshould never be known to anybody; nor should they know oneanother.
When they propose anything very material, secure theirpersons, or have in your possession their wives and children ashostages
for their fidelity. Never communicate anything to thembut what is absolutely necessary that they should know. [2] ]

15.
Spies cannot be usefully employed without a certainintuitive sagacity.

[Mei Yao-ch`en says: "In order to use them,
one must knowfact from falsehood, and be able to discriminate between honestyand double-dealing." Wang Hsi in a different
interpretationthinks more along the lines of "intuitive perception" and"practical intelligence." Tu Mu strangely refers
theseattributes to the spies themselves: "Before using spies we mustassure ourselves as to their integrity of character
and theextent of their experience and skill." But he continues: "Abrazen face and a crafty disposition are more dangerous
thanmountains or rivers; it takes a man of genius to penetrate such."

So that we are left in some doubt as to his
real opinion on thepassage."]

16. They cannot be properly managed without benevolence andstraightforwardness.

[Chang
Yu says: "When you have attracted them bysubstantial offers, you must treat them with absolute sincerity;then they
will work for you with all their might."]

17. Without subtle ingenuity of mind, one cannot makecertain of the truth
of their reports.

[Mei Yao-ch`en says: "Be on your guard against thepossibility of spies going over to the service
of the enemy."]

18. Be subtle! be subtle! and use your spies for every kindof business.

[Cf. VI. ss. 9.]

19.
If a secret piece of news is divulged by a spy beforethe time is ripe, he must be put to death together with the manto
whom the secret was told.

[Word for word, the translation here is: "If spy mattersare heard before [our plans]
are carried out," etc. Sun Tzu'smain point in this passage is: Whereas you kill the spy himself"as a punishment for
letting out the secret," the object ofkilling the other man is only, as Ch`en Hao puts it, "to stop hismouth" and
prevent news leaking any further. If it had alreadybeen repeated to others, this object would not be gained. Eitherway,
Sun Tzu lays himself open to the charge of inhumanity,though Tu Mu tries to defend him by saying that the man deservesto
be put to death, for the spy would certainly not have told thesecret unless the other had been at pains to worm it out
ofhim."]

20. Whether the object be to crush an army, to storm acity, or to assassinate an individual, it is
always necessary tobegin by finding out the names of the attendants, the aides-de-camp,

[Literally "visitors",
is equivalent, as Tu Yu says, to"those whose duty it is to keep the general supplied withinformation," which naturally
necessitates frequent interviewswith him.]and door-keepers and sentries of the general in command. Ourspies must
be commissioned to ascertain these.

[As the first step, no doubt towards finding out if any ofthese important functionaries
can be won over by bribery.]

21. The enemy's spies who have come to spy on us must besought out, tempted with bribes,
led away and comfortably housed.

Thus they will become converted spies and available for ourservice.22. It
is through the information brought by the convertedspy that we are able to acquire and employ local and inwardspies.

[Tu
Yu says: "through conversion of the enemy's spies welearn the enemy's condition." And Chang Yu says: "We must temptthe
converted spy into our service, because it is he that knowswhich of the local inhabitants are greedy of gain, and which
ofthe officials are open to corruption."]

23. It is owing to his information, again, that we cancause the doomed
spy to carry false tidings to the enemy.

[Chang Yu says, "because the converted spy knows how theenemy can best
be deceived."]

24. Lastly, it is by his information that the surviving spycan be used on appointed occasions.25.
The end and aim of spying in all its five varieties isknowledge of the enemy; and this knowledge can only be derived,in
the first instance, from the converted spy.

[As explained in ss. 22-24. He not only brings informationhimself,
but makes it possible to use the other kinds of spy toadvantage.]

Hence it is essential that the converted spy
be treated with theutmost liberality.26. Of old, the rise of the Yin dynasty

[Sun Tzu means the Shang dynasty,
founded in 1766 B.C. Itsname was changed to Yin by P`an Keng in 1401.

was due to I Chih

[Better known as
I Yin, the famous general and statesmanwho took part in Ch`eng T`ang's campaign against Chieh Kuei.]

who had served
under the Hsia. Likewise, the rise of the Choudynasty was due to Lu Ya

[Lu Shang rose to high office under the
tyrant Chou Hsin,whom he afterwards helped to overthrow. Popularly known as T`aiKung, a title bestowed on him by Wen
Wang, he is said to havecomposed a treatise on war, erroneously identified with theLIU T`AO.]

who had served
under the Yin.

[There is less precision in the Chinese than I have thoughtit well to introduce into my translation,
and the commentaries onthe passage are by no means explicit. But, having regard to thecontext, we can hardly doubt
that Sun Tzu is holding up I Chihand Lu Ya as illustrious examples of the converted spy, orsomething closely analogous.
His suggestion is, that the Hsiaand Yin dynasties were upset owing to the intimate knowledge oftheir weaknesses and
shortcoming which these former ministerswere able to impart to the other side. Mei Yao-ch`en appears toresent any
such aspersion on these historic names: "I Yin and LuYa," he says, "were not rebels against the Government. Hsiacould
not employ the former, hence Yin employed him. Yin couldnot employ the latter, hence Hou employed him. Their greatachievements
were all for the good of the people." Ho Shih isalso indignant: "How should two divinely inspired men such as Iand
Lu have acted as common spies? Sun Tzu's mention of themsimply means that the proper use of the five classes of spies
isa matter which requires men of the highest mental caliber like Iand Lu, whose wisdom and capacity qualified them
for the task.The above words only emphasize this point." Ho Shih believesthen that the two heroes are mentioned on
account of theirsupposed skill in the use of spies. But this is very weak.]

27. Hence it is only the enlightened
ruler and the wisegeneral who will use the highest intelligence of the army forpurposes of spying and thereby they
achieve great results.

[Tu Mu closes with a note of warning: "Just as water, whichcarries a boat from bank to bank,
may also be the means ofsinking it, so reliance on spies, while production of greatresults, is oft-times the cause
of utter destruction."]

Spies are a most important element in water, because on themdepends an army's ability to
move.

[Chia Lin says that an army without spies is like a man withears or eyes.]

1.
Sun Tzu said: Raising a host of a hundred thousand menand marching them great distances entails heavy loss on thepeople
and a drain on the resources of the State. The dailyexpenditure will amount to a thousand ounces of silver.

[Cf.
II. ss. ss. 1, 13, 14.]

There will be commotion at home and abroad, and men will dropdown exhausted on the highways.

"We
may be reminded of the saying: 'On serious ground, gather inplunder.' Why then should carriage and transportation causeexhaustion
on the highways?--The answer is, that not victualsalone, but all sorts of munitions of war have to be conveyed tothe
army. Besides, the injunction to 'forage on the enemy' onlymeans that when an army is deeply engaged in hostile territory,scarcity
of food must be provided against. Hence, without beingsolely dependent on the enemy for corn, we must forage in orderthat
there may be an uninterrupted flow of supplies. Then,again, there are places like salt deserts where provisions beingunobtainable,
supplies from home cannot be dispensed with."]

As many as seven hundred thousand families will be impeded intheir
labor.

[Mei Yao-ch`en says: "Men will be lacking at the plough-tail." The allusion is to the system of dividing
land into nineparts, each consisting of about 15 acres, the plot in the centerbeing cultivated on behalf of the State
by the tenants of theother eight. It was here also, so Tu Mu tells us, that theircottages were built and a well sunk,
to be used by all in common.

[See II. ss. 12, note.] In time of war, one of the families hadto serve in the army,
while the other seven contributed to itssupport. Thus, by a levy of 100,000 men (reckoning one able-bodied soldier
to each family) the husbandry of 700,000 familieswould be affected.]

2. Hostile armies may face each other for
years, strivingfor the victory which is decided in a single day. This being so,to remain in ignorance of the enemy's
condition simply becauseone grudges the outlay of a hundred ounces of silver in honorsand emoluments,

["For
spies" is of course the meaning, though it would spoilthe effect of this curiously elaborate exordium if spies wereactually
mentioned at this point.]

is the height of inhumanity.

[Sun Tzu's agreement is certainly ingenious. He begins
byadverting to the frightful misery and vast expenditure of bloodand treasure which war always brings in its train.
Now, unlessyou are kept informed of the enemy's condition, and are ready tostrike at the right moment, a war may drag
on for years. Theonly way to get this information is to employ spies, and it isimpossible to obtain trustworthy spies
unless they are properlypaid for their services. But it is surely false economy togrudge a comparatively trifling
amount for this purpose, whenevery day that the war lasts eats up an incalculably greater sum.

This grievous burden
falls on the shoulders of the poor, andhence Sun Tzu concludes that to neglect the use of spies isnothing less than
a crime against humanity.]

3. One who acts thus is no leader of men, no present helpto his sovereign, no master
of victory.

[This idea, that the true object of war is peace, has itsroot in the national temperament of the Chinese.
Even so farback as 597 B.C., these memorable words were uttered by PrinceChuang of the Ch`u State: "The [Chinese]
character for 'prowess'is made up of [the characters for] 'to stay' and 'a spear'(cessation of hostilities). Military
prowess is seen in therepression of cruelty, the calling in of weapons, thepreservation of the appointment of Heaven,
the firm establishmentof merit, the bestowal of happiness on the people, puttingharmony between the princes, the diffusion
of wealth."]

4. Thus, what enables the wise sovereign and the goodgeneral to strike and conquer, and achieve things
beyond thereach of ordinary men, is FOREKNOWLEDGE.

[That is, knowledge of the enemy's dispositions, and what hemeans
to do.]

5. Now this foreknowledge cannot be elicited from spirits;it cannot be obtained inductively from experience,

[Tu
Mu's note is: "[knowledge of the enemy] cannot begained by reasoning from other analogous cases."]

nor by any deductive
calculation.

[Li Ch`uan says: "Quantities like length, breadth,distance and magnitude, are susceptible of exact
mathematicaldetermination; human actions cannot be so calculated."]

6. Knowledge of the enemy's dispositions can
only beobtained from other men.

[Mei Yao-ch`en has rather an interesting note: "Knowledgeof the spirit-world
is to be obtained by divination; informationin natural science may be sought by inductive reasoning; the lawsof the
universe can be verified by mathematical calculation: butthe dispositions of an enemy are ascertainable through spies
andspies alone."]

7. Hence the use of spies, of whom there are five classes:(1) Local spies; (2) inward spies;
(3) converted spies; (4)doomed spies; (5) surviving spies.8. When these five kinds of spy are all at work, none candiscover
the secret system. This is called "divine manipulationof the threads." It is the sovereign's most precious faculty.

[Cromwell,
one of the greatest and most practical of allcavalry leaders, had officers styled 'scout masters,' whosebusiness it
was to collect all possible information regarding theenemy, through scouts and spies, etc., and much of his success inwar
was traceable to the previous knowledge of the enemy's movesthus gained." [1] ]

9. Having LOCAL SPIES means employing
the services of theinhabitants of a district.

[Tu Mu says: "In the enemy's country, win people over bykind
treatment, and use them as spies."]

10. Having INWARD SPIES, making use of officials of theenemy.

[Tu Mu
enumerates the following classes as likely to do goodservice in this respect: "Worthy men who have been degraded fromoffice,
criminals who have undergone punishment; also, favoriteconcubines who are greedy for gold, men who are aggrieved atbeing
in subordinate positions, or who have been passed over inthe distribution of posts, others who are anxious that their
sideshould be defeated in order that they may have a chance ofdisplaying their ability and talents, fickle turncoats
who alwayswant to have a foot in each boat. Officials of these severalkinds," he continues, "should be secretly approached
and bound toone's interests by means of rich presents. In this way you willbe able to find out the state of affairs
in the enemy's country,ascertain the plans that are being formed against you, andmoreover disturb the harmony and
create a breach between thesovereign and his ministers." The necessity for extreme caution,however, in dealing with
"inward spies," appears from anhistorical incident related by Ho Shih: "Lo Shang, Governor ofI-Chou, sent his general
Wei Po to attack the rebel Li Hsiung ofShu in his stronghold at P`i. After each side had experienced anumber of victories
and defeats, Li Hsiung had recourse to theservices of a certain P`o-t`ai, a native of Wu-tu. He began tohave him whipped
until the blood came, and then sent him off toLo Shang, whom he was to delude by offering to cooperate with himfrom
inside the city, and to give a fire signal at the rightmoment for making a general assault. Lo Shang, confiding inthese
promises, march out all his best troops, and placed Wei Poand others at their head with orders to attack at P`o-t`ai'sbidding.
Meanwhile, Li Hsiung's general, Li Hsiang, had preparedan ambuscade on their line of march; and P`o-t`ai, having rearedlong
scaling-ladders against the city walls, now lighted thebeacon-fire. Wei Po's men raced up on seeing the signal andbegan
climbing the ladders as fast as they could, while otherswere drawn up by ropes lowered from above. More than a hundredof
Lo Shang's soldiers entered the city in this way, every one ofwhom was forthwith beheaded. Li Hsiung then charged with
all hisforces, both inside and outside the city, and routed the enemycompletely." [This happened in 303 A.D. I do
not know where HoShih got the story from. It is not given in the biography of LiHsiung or that of his father Li T`e,
CHIN SHU, ch. 120, 121.]

11. Having CONVERTED SPIES, getting hold of the enemy'sspies and using them for our own
purposes.

[By means of heavy bribes and liberal promises detachingthem from the enemy's service, and inducing them
to carry backfalse information as well as to spy in turn on their owncountrymen. On the other hand, Hsiao Shih-hsien
says that wepretend not to have detected him, but contrive to let him carryaway a false impression of what is going
on. Several of thecommentators accept this as an alternative definition; but thatit is not what Sun Tzu meant is conclusively
proved by hissubsequent remarks about treating the converted spy generously(ss. 21 sqq.). Ho Shih notes three occasions
on which convertedspies were used with conspicuous success: (1) by T`ien Tan inhis defense of Chi-mo (see supra, p.
90); (2) by Chao She on hismarch to O-yu (see p. 57); and by the wily Fan Chu in 260 B.C.,when Lien P`o was conducting
a defensive campaign against Ch`in.The King of Chao strongly disapproved of Lien P`o's cautious anddilatory methods,
which had been unable to avert a series ofminor disasters, and therefore lent a ready ear to the reports ofhis spies,
who had secretly gone over to the enemy and werealready in Fan Chu's pay. They said: "The only thing whichcauses Ch`in
anxiety is lest Chao Kua should be made general.Lien P`o they consider an easy opponent, who is sure to bevanquished
in the long run." Now this Chao Kua was a sun of thefamous Chao She. From his boyhood, he had been wholly engrossedin
the study of war and military matters, until at last he cameto believe that there was no commander in the whole Empire
whocould stand against him. His father was much disquieted by thisoverweening conceit, and the flippancy with which
he spoke ofsuch a serious thing as war, and solemnly declared that if everKua was appointed general, he would bring
ruin on the armies ofChao. This was the man who, in spite of earnest protests fromhis own mother and the veteran statesman
Lin Hsiang-ju, was nowsent to succeed Lien P`o. Needless to say, he proved no matchfor the redoubtable Po Ch`i and
the great military power ofCh`in. He fell into a trap by which his army was divided intotwo and his communications
cut; and after a desperate resistancelasting 46 days, during which the famished soldiers devoured oneanother, he was
himself killed by an arrow, and his whole force,amounting, it is said, to 400,000 men, ruthlessly put to thesword.]

12.
Having DOOMED SPIES, doing certain things openly forpurposes of deception, and allowing our spies to know of them andreport
them to the enemy.

[Tu Yu gives the best exposition of the meaning: "Weostentatiously do thing calculated to deceive
our own spies, whomust be led to believe that they have been unwittingly disclosed.

Then, when these spies are
captured in the enemy's lines, theywill make an entirely false report, and the enemy will takemeasures accordingly,
only to find that we do something quitedifferent. The spies will thereupon be put to death." As anexample of doomed
spies, Ho Shih mentions the prisoners releasedby Pan Ch`ao in his campaign against Yarkand. (See p. 132.) Healso refers
to T`ang Chien, who in 630 A.D. was sent by T`aiTsung to lull the Turkish Kahn Chieh-li into fancied security,until
Li Ching was able to deliver a crushing blow against him.Chang Yu says that the Turks revenged themselves by killing T`angChien,
but this is a mistake, for we read in both the old and theNew T`ang History (ch. 58, fol. 2 and ch. 89, fol. 8respectively)
that he escaped and lived on until 656. Li I-chiplayed a somewhat similar part in 203 B.C., when sent by the Kingof
Han to open peaceful negotiations with Ch`i. He has certainlymore claim to be described a "doomed spy", for the king of
Ch`i,being subsequently attacked without warning by Han Hsin, andinfuriated by what he considered the treachery of
Li I-chi,ordered the unfortunate envoy to be boiled alive.]

13. SURVIVING SPIES, finally, are those who bring back
newsfrom the enemy's camp.

[This is the ordinary class of spies, properly so called,forming a regular part
of the army. Tu Mu says: "Your survivingspy must be a man of keen intellect, though in outward appearancea fool; of
shabby exterior, but with a will of iron. He must beactive, robust, endowed with physical strength and courage;thoroughly
accustomed to all sorts of dirty work, able to endurehunger and cold, and to put up with shame and ignominy." Ho Shihtells
the following story of Ta`hsi Wu of the Sui dynasty: "Whenhe was governor of Eastern Ch`in, Shen-wu of Ch`i made a hostilemovement
upon Sha-yuan. The Emperor T`ai Tsu [? Kao Tsu] sentTa-hsi Wu to spy upon the enemy. He was accompanied by two othermen.
All three were on horseback and wore the enemy's uniform.When it was dark, they dismounted a few hundred feet away fromthe
enemy's camp and stealthily crept up to listen, until theysucceeded in catching the passwords used in the army. Then theygot
on their horses again and boldly passed through the campunder the guise of night-watchmen; and more than once, happeningto
come across a soldier who was committing some breach ofdiscipline, they actually stopped to give the culprit a soundcudgeling!
Thus they managed to return with the fullest possibleinformation about the enemy's dispositions, and received warmcommendation
from the Emperor, who in consequence of their reportwas able to inflict a severe defeat on his adversary."]

14.
Hence it is that which none in the whole army are moreintimate relations to be maintained than with spies.

[Tu
Mu and Mei Yao-ch`en point out that the spy isprivileged to enter even the general's private sleeping-tent.]

None
should be more liberally rewarded. In no other businessshould greater secrecy be preserved.

[Tu Mu gives a graphic
touch: all communication with spiesshould be carried "mouth-to-ear." The following remarks on spiesmay be quoted from
Turenne, who made perhaps larger use of themthan any previous commander: "Spies are attached to those whogive them
most, he who pays them ill is never served. Theyshould never be known to anybody; nor should they know oneanother.
When they propose anything very material, secure theirpersons, or have in your possession their wives and children ashostages
for their fidelity. Never communicate anything to thembut what is absolutely necessary that they should know. [2] ]

15.
Spies cannot be usefully employed without a certainintuitive sagacity.

[Mei Yao-ch`en says: "In order to use them,
one must knowfact from falsehood, and be able to discriminate between honestyand double-dealing." Wang Hsi in a different
interpretationthinks more along the lines of "intuitive perception" and"practical intelligence." Tu Mu strangely refers
theseattributes to the spies themselves: "Before using spies we mustassure ourselves as to their integrity of character
and theextent of their experience and skill." But he continues: "Abrazen face and a crafty disposition are more dangerous
thanmountains or rivers; it takes a man of genius to penetrate such."

So that we are left in some doubt as to his
real opinion on thepassage."]

16. They cannot be properly managed without benevolence andstraightforwardness.

[Chang
Yu says: "When you have attracted them bysubstantial offers, you must treat them with absolute sincerity;then they
will work for you with all their might."]

17. Without subtle ingenuity of mind, one cannot makecertain of the truth
of their reports.

[Mei Yao-ch`en says: "Be on your guard against thepossibility of spies going over to the service
of the enemy."]

18. Be subtle! be subtle! and use your spies for every kindof business.

[Cf. VI. ss. 9.]

19.
If a secret piece of news is divulged by a spy beforethe time is ripe, he must be put to death together with the manto
whom the secret was told.

[Word for word, the translation here is: "If spy mattersare heard before [our plans]
are carried out," etc. Sun Tzu'smain point in this passage is: Whereas you kill the spy himself"as a punishment for
letting out the secret," the object ofkilling the other man is only, as Ch`en Hao puts it, "to stop hismouth" and
prevent news leaking any further. If it had alreadybeen repeated to others, this object would not be gained. Eitherway,
Sun Tzu lays himself open to the charge of inhumanity,though Tu Mu tries to defend him by saying that the man deservesto
be put to death, for the spy would certainly not have told thesecret unless the other had been at pains to worm it out
ofhim."]

20. Whether the object be to crush an army, to storm acity, or to assassinate an individual, it is
always necessary tobegin by finding out the names of the attendants, the aides-de-camp,

[Literally "visitors",
is equivalent, as Tu Yu says, to"those whose duty it is to keep the general supplied withinformation," which naturally
necessitates frequent interviewswith him.]and door-keepers and sentries of the general in command. Ourspies must
be commissioned to ascertain these.

[As the first step, no doubt towards finding out if any ofthese important functionaries
can be won over by bribery.]

21. The enemy's spies who have come to spy on us must besought out, tempted with bribes,
led away and comfortably housed.

Thus they will become converted spies and available for ourservice.22. It
is through the information brought by the convertedspy that we are able to acquire and employ local and inwardspies.

[Tu
Yu says: "through conversion of the enemy's spies welearn the enemy's condition." And Chang Yu says: "We must temptthe
converted spy into our service, because it is he that knowswhich of the local inhabitants are greedy of gain, and which
ofthe officials are open to corruption."]

23. It is owing to his information, again, that we cancause the doomed
spy to carry false tidings to the enemy.

[Chang Yu says, "because the converted spy knows how theenemy can best
be deceived."]

24. Lastly, it is by his information that the surviving spycan be used on appointed occasions.25.
The end and aim of spying in all its five varieties isknowledge of the enemy; and this knowledge can only be derived,in
the first instance, from the converted spy.

[As explained in ss. 22-24. He not only brings informationhimself,
but makes it possible to use the other kinds of spy toadvantage.]

Hence it is essential that the converted spy
be treated with theutmost liberality.26. Of old, the rise of the Yin dynasty

[Sun Tzu means the Shang dynasty,
founded in 1766 B.C. Itsname was changed to Yin by P`an Keng in 1401.

was due to I Chih

[Better known as
I Yin, the famous general and statesmanwho took part in Ch`eng T`ang's campaign against Chieh Kuei.]

who had served
under the Hsia. Likewise, the rise of the Choudynasty was due to Lu Ya

[Lu Shang rose to high office under the
tyrant Chou Hsin,whom he afterwards helped to overthrow. Popularly known as T`aiKung, a title bestowed on him by Wen
Wang, he is said to havecomposed a treatise on war, erroneously identified with theLIU T`AO.]

who had served
under the Yin.

[There is less precision in the Chinese than I have thoughtit well to introduce into my translation,
and the commentaries onthe passage are by no means explicit. But, having regard to thecontext, we can hardly doubt
that Sun Tzu is holding up I Chihand Lu Ya as illustrious examples of the converted spy, orsomething closely analogous.
His suggestion is, that the Hsiaand Yin dynasties were upset owing to the intimate knowledge oftheir weaknesses and
shortcoming which these former ministerswere able to impart to the other side. Mei Yao-ch`en appears toresent any
such aspersion on these historic names: "I Yin and LuYa," he says, "were not rebels against the Government. Hsiacould
not employ the former, hence Yin employed him. Yin couldnot employ the latter, hence Hou employed him. Their greatachievements
were all for the good of the people." Ho Shih isalso indignant: "How should two divinely inspired men such as Iand
Lu have acted as common spies? Sun Tzu's mention of themsimply means that the proper use of the five classes of spies
isa matter which requires men of the highest mental caliber like Iand Lu, whose wisdom and capacity qualified them
for the task.The above words only emphasize this point." Ho Shih believesthen that the two heroes are mentioned on
account of theirsupposed skill in the use of spies. But this is very weak.]

27. Hence it is only the enlightened
ruler and the wisegeneral who will use the highest intelligence of the army forpurposes of spying and thereby they
achieve great results.

[Tu Mu closes with a note of warning: "Just as water, whichcarries a boat from bank to bank,
may also be the means ofsinking it, so reliance on spies, while production of greatresults, is oft-times the cause
of utter destruction."]

Spies are a most important element in water, because on themdepends an army's ability to
move.

[Chia Lin says that an army without spies is like a man withears or eyes.]